Ridgelines are super convenient for hanging things. Number one on that list would be a bug net. People also make pouches that hook to the ridgeline for putting eyeglasses, headlamps, etc. They call these "ridgeline organizers:"
You can make a ridgleine out of just about anything. BUT, keep in mind that, depending in the way you hang the hammock, you could have a few hundred pounds of tension on the line. The "proper" way to hang with a ridgline is to have just enough tension on it to keep it straight, but no more. However, I've seen people hang from trees that are too far apart and snap a 500 pound test ridgeline. If you plan to do this, go with dynaglide or amsteel.
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